A-87-126
NTSB Safety Recommendation — Aviation
Recommendation text
THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: ISSUE AN AIRWORTHINESS DIRECTIVE REQUIRING OPERATORS OF BOEING 737-100 AND -200 AIRPLANES TO PERIODICALLY INSPECT THE THREAD RELIEF UNDERCUT RADIUS OF THE AFT CONE ATTACHMENT BOLT OF EACH ENGINE FOR EVIDENCE OF CRACKING; SUCH INSPECTIONS SHOULD BE AT SERVICE TIME INTERVALS THAT WILL ENSURE THAT A FATIGUE CRACK IN THE BOLT WILL NOT PROPAGATE TO A CRITICAL CRACK LENGTH BEFORE DETECTION.
In plain language (FlightFinder summary)
The NTSB asks the FAA to issue an airworthiness directive requiring operators of Boeing 737-100 and -200 airplanes to periodically inspect the thread relief undercut radius of each engine's aft cone attachment bolt for cracks. Inspections must be scheduled at service intervals that ensure a fatigue crack will not grow to a critical length before it is detected.
This plain-language summary is written by FlightFinder to explain the recommendation above. It is not the official wording — the verbatim NTSB text is quoted above.
Details
| Status | Closed - Acceptable Action |
|---|---|
| Mode | Aviation |
| Closed | May 11, 1988 |
| NTSB number | NYC88FA050 |
| Addressees | FAA |
External links
NTSB safety recommendations are advisory; addressees are not legally required to adopt them. Source: NTSB CAROL (public domain).